city vs St. John

city and St. John both are nouns.

Word	Noun	Adjective	Verb	Adverb
city	Yes	No	No	No
St. John	Yes	No	No	No

city (noun)	St. John (noun)
people living in a large densely populated municipality	a port in eastern Canada; the largest city in New Brunswick
a large and densely populated urban area; may include several independent administrative districts	a river that rises in Maine and flows northeastward through New Brunswick to empty into the Bay of Fundy
an incorporated administrative district established by state charter	(New Testament) disciple of Jesus; traditionally said to be the author of the 4th Gospel and three epistles and the book of Revelation